Project Summary/Abstract Despite being one of the largest and fastest-growing demographics in the United States (US), Latinos experience striking health disparities, particularly in the area of alcohol use. One possible reason for this is that Latinos are disproportionately affected by stressful life conditions, notably poverty and discrimination, which may lead to higher rates of alcohol consumption and alcohol-related problems (i.e., problematic alcohol use). Subtle discrimination at the daily-level, known as racial/ethnic microaggressions, are common among Latinos, and may account for significant and unique variance in problematic alcohol use within this population. The proposed study will use randomly signaled ecological momentary assessment (EMA) over a 10-day period, to study the impact of microaggressions on Latinos alcohol consumption and alcohol-related problems. Furthermore, it will determine the underlying processes that account for this relationship, and test theoretically-driven risk and resilience factors. One-hundred low-income Latinos will be recruited from a Federally-Qualified Health Center (FQHC) to complete baseline questionnaires, and then participate in the EMA phase of the study. At baseline, participants will complete demographics, measures of traditional Latino cultural values and a Stress and Adversity Inventory (STRAIN), give a blood sample to assess chronic stress with levels of high sensitivity C-reactive protein (CRP), and report on problematic alcohol use. In randomly signaled reports three times a day, participants will report experiences of microaggressions, non-discriminatory life stressors, stress, inhibitory control, failure to seek out similar others, as well as problematic alcohol use. This proposal can significantly advance our knowledge of precursors to problematic alcohol use within the Latino community, and provide critical insight for future prevention and intervention programs. The proposed research project supports the 2017-2021 strategic plan of the National Institute of National Institute on Alcohol Abuse and Alcoholism (NIAAA) by advancing research in 2 of the key areas. First, the current proposal has the end goal of improving strategies to prevent alcohol misuse, alcohol use disorder, and alcohol-related consequences, by targeting a population known to be at risk for both (goal 3). Second, it enhances the public health impact of NIAAA-supported research, by focusing on one of the fastest-growing and largest demographics in the US who demonstrate disparities in alcohol misuse (goal 5). Furthermore, the proposal contributes to research on health disparities, one of the cross-cutting research themes of NIAAA. The findings of this project will be disseminated to researchers, education administrators, students, policy makers, and the public. The award and completion of this project will afford substantial training in ethics, methodologies, statistics, and writing, to a promising young researcher and will address the significant need for innovative research on problematic alcohol use in an underserved population.